Drop embedded jemalloc

The embedded jemalloc we ship is outdated and jemalloc is now
generally available in distributions, so stop shipping our own copy.
Handle input from stdin properly in varnishadm

readline doesn't really handle when input comes from a file or pipe,
so only use readline if stdin is a tty.

Thanks to johnnyrun for a patch which was used for inspiration here.

Fixes #1314
Clear up time to first byte description in varnishncsa man page

Fixes #1305
Fix path in initscript

Thanks to shin1x1 for the patch.
copy-edits
https://github.com/varnish/Varnish-Cache/pull/13

by xiongchiamiov
typo and whitespace
https://github.com/varnish/Varnish-Cache/pull/16

by psa
doc .initial
https://github.com/varnish/Varnish-Cache/pull/14
Reset vsl_log.wid in VSL_Setup.

This ensures that background threads like expire and ban lurker logs
using ID 0.
Fix memory leak on multiple -n / -N options
Add a VSLQ_Name2Grouping function to parse -g arguments
Add vut.[ch] to hold functions common to the utilities.

Move some parsing of options to these files.
Add VSL_Write* functions for writing binary log output.
Fix up the binary file reading VSL cursor
Enable binary file reading and writing in varnishlog
Add a VUT_Main implementation that all the VSL utilities should be
able to use.

Moved most functionality from varnishlog to VUT.
Document the varnish API options in a single place, using preprocessor
tables.

Enhance the usage() output of varnishlog using the new tables.

Add API utility header to extract data from the option headers.
Make the option documentation be generated from the option tables.
Add a lib/libvarnishtools library to hold common files for the tools.

Move vut.c and opt2rst.c there.
Let the synopsis be generated from the option table files
Add -P (PID-file) and -D (daemon mode) options to the utilities libraries.

Make varnishlog use these options.