This fixes the following error received on OpenBSD when running `install.sh`.

```
$ sh install.sh
Copying fonts...
cp: cannot stat '%': No such file or directory
All Powerline fonts installed to /home/foo/.local/share/fonts
```

What's happening is that OpenBSD's `xargs` fails without the `-n1` option (i.e. copy the files one-at-a-time).

Adding the `-n1` seems to be compatible with Linux (I tried it on a CentOS system); probably holds for Mac OS X too (but I don't have one to test on).

This commit allows the user to specify a subset of fonts to install e.g. ./install.ps1 fura-*,hack-* will install all the FuraMono and Hack fonts. Support for the -WhatIf parameter was also added so you can see what fonts would be installed (without actually installing the fonts).

The current patched version of Meslo has fi and ff ligatures. I used a
patched version of powerline-fontpatcher to fix this. I have also
included a patched dotted version of Meslo.

Update cousine font source link

only try fc-cache reset on linux

Fixed wrong fonts directory in install.sh

Link to Powerline

add windows install script

Adding Croscore fonts (Chrome OS core fonts)

updated Hack fonts with Powerline glyph alignment adjustments

Add pre-patched Roboto Mono font

fc-cache doesn't exist on osx :)

add windows install script

Resolves #116

added image links for Hack font

add Hack fonts

Add pre-patched Droid Sans Mono Slashed and Dotted fonts

Added a file that includes all the samples.

compare the qualities of the different fonts.

Add font sample screenshots

Add FuraMono (FiraMono derivative)

Fixes #67

Monofur font added

Allow spaces in powerline fonts source dir

Update install.sh

Further testing shows that the find command fails for GNU find under Ubuntu 11.10 and EL6.

This script was only copying over the pcf.gz files on OSX 10.9 and 10.10 since the find command is a little different.

install.sh should also install Terminus font extension (pcf.gz)