rename 'ini.go' to 'config.go' and refactor configuration parsing.
added zip support, now can read source files from a zip package
revise 'README.md' to make it compatible with github
Refactor
log messages to stderr instead of stdout

changed the log output from stdout to stderr. and refactor the error
handling logic, this is prepare for adding new features, like batch
processing.
batch mode added

in batch mode, user can specify a batch file(a text file, one line for one
book) or a folder(will conver the zip files in it and the direct
sub-folders) to process multiple books at one time.

the document is not updated yet.
added the new files that should be added in last commit
add the feature to extract an EPUB

use 'makeepub -e epub output_folder' to extract the EPUB file to the
output folder.
can also be used to extract zip files :).
add the feature to merge html files

command line: makeepub <input_folder> <output_file>
will merge the files in the input folder into a single file named
'output_file'. there should be only html files in the input folder,
otherwise the behavior is undefined. the files will be merged in the order
of their names.
added feature pack

now can use 'makeepub -p <source> <target>' to pack a folder or zip file
into an epub.
refactor, will do more refactor later
refactor, rename 'IFileRepo' to 'InputFolder'
continue refactor

'merge' now support input from zip file
use 'bufio.Scanner' instead of 'bufio.Reader'
refactor, and make ZipFolder support memory data
refactor and minor improvement

'merge' now support text files
optimization for performance
refactor

when making a book, can write log to 'file' other than stderr.
when making a book, the result can be output to memory
the last refactor, ready for add the 'server' feature

rename InputFolder to VirtualFolder
added server mode

user 'makeepub -s [port]' to run as a http server.
revised 'usage' string to align with feature

also fix a minor bug in handling command line switch.
updated manual and examples