README: Add new and updated sections.

* README.md:(Requirements): Add it.
(License): Add it.
(Documentation): Remove it.
(Installation): Add Ubuntu and Fedora issue.
(How to contribute): Rename to Contributing and add a section for
building.

README.md

@@ -3,17 +3,20 @@
 Guile-Git is a GNU Guile library providing bindings to
 [libgit2](https://libgit2.org/).
 
-Copyright © 2016, 2017 Amirouche Boubekki
-Copyright © 2018 Erik Edrosa
+Copyright © 2016, 2017 Amirouche Boubekki  
+Copyright © 2018, 2019 Erik Edrosa  
 Copying and distribution of this file, with or without modification,
 are permitted in any medium without royalty provided the copyright
 notice and this notice are preserved.  This file is offered as-is,
 without any warranty.
 
-## Documentation
+## Requirements
 
-The documentation is currently a work in progress, so please read the
-source and have a look at the [libgit2 API](https://libgit2.org/libgit2/#HEAD).
+Guile-Git requires the following to be installed.
+
+- [GNU Guile](https://www.gnu.org/software/guile/) >= 2.0.11
+- [libgit2](https://libgit2.org/)
+- [scheme-bytestructures](https://github.com/TaylanUB/scheme-bytestructures)
 
 ## Installation
 
@@ -39,7 +42,19 @@ export GUILE_LOAD_PATH="/usr/local/share/guile/site/2.2${GUILE_LOAD_PATH:+:}$GUI
 export GUILE_LOAD_COMPILED_PATH="/usr/local/lib/guile/2.2/site-ccache${GUILE_LOAD_COMPILED_PATH:+:}$GUILE_COMPILED_LOAD_PATH"
 ```
 
-## How to contribute
+A common issue you may encounter when installing, especially on Ubuntu
+and Fedora, is guild not being found when you run `configure`. This
+happens because the configure script finds a symbolic link to a
+version of guile with a version number, like guile-2.2. This then has
+the configure script check for guild-2.2 which does not exist. To fix
+this, you can provide the path to the version of guile you want to
+install it for.
+
+```sh
+./configure GUILE=$(which guile)
+```
+
+## Contributing
 
 The easiest way to start hacking on guile-git is to install
 [GNU Guix](https://gnu.org/s/guix) and run the following command:
@@ -48,6 +63,20 @@ The easiest way to start hacking on guile-git is to install
 > guix environment -l guix.scm
 ```
 
+To build from git you do:
+
+```sh
+./bootstrap
+./configure
+make
+```
+
+To run the unit tests you do:
+
+```sh
+make check
+```
+
 You can then:
 
 - Create a pull request on gitlab
@@ -55,3 +84,8 @@ You can then:
 - Come and ping `OrangeShark` about it at `#guile@irc.freenode.net`.
 
 And don't forget to add a unit test!
+
+## License
+
+Guile-Git is licenced under GPLv3 or later. See COPYING file for
+details.
\ No newline at end of file